Alkylbenzene sulfonate detergent compositions containing 2-hydroxy-1-amino alkanes



United States Patent 3,296,146 ALKYLBENZENE SULFONATE DETERGENT COM- POSITIONS CONTAINING Z-HYDROXY-l-AMINO ALKANES Joseph A. Meyers, Springfield, Pa., Edward G. Shay, Belle Mead, N.J., and Robert C. Taylor, King of Prussia, Pa., assignors to Atlantic Richfield Company, a corporation of Pennsylvania No Drawing. Fiied Aug. 26, 1965, Ser. No. 482,920 14 Claims. (Cl. 252137) This invention relates to a detergent composition having improved detergency properties and more particularly to alkylbenzene sulfonate detergent compositions containing a detergency improving agent.

Water soluble alkylbenzene sulfonates wherein the alkyl group contains 9 to 15 carbon atoms are well known and widely used as the active detergent ingredient in synthetic detergent compositions. It is known to improve the detergency properties of these compositions by adding thereto small amounts of a detergency improvwherein R is an alkyl radical having from about 4 to about 18 carbon atoms and wherein this detergency improving agent is present in the composition in an amount ranging from about 0.3 weight percent to about 3.3 weight percent based on the amount of the Water soluble alkylbenzene sulfonate present in the composition. In the preferred practice of this invention the above described hydroxy amino alkane is utilized to improve the detergency properties of a built alkylbenzene sulfonate detergent composition and accordingly such a composition is comprised of, in weight percent based on the total weight of the composition, (a) about to about 30 percent of a water soluble alkylbenzene sulfonate having from 9 to carbon atoms in the alkyl chain, (b) about 0.03 to about 1.0 percent of 2-hydroxy-1-amino alkane of the above formula wherein the hydroxy amino alkane is present in an amount ranging from about 0.3 to about 3.3 weight percent of the alkylbenzene sulfonate and (c) about 70 to about 90 percent of detergent builders.

The alkylbenzene sulfonates which are utilized as the active detergent component in the compositions of this invention and which have their detergency qualities improved by the addition thereto of 2-hydroxy-1-amino alkanes are any water soluble alkylbenzene sulfonates which have 9 to 15 carbon atoms in the alkyl chain. The alkyl group attached to the benzene ring may be either straight or branched in structure. Whereas it is preferred to utilize sodium alkylbenzene sulfonate as the active detergent ingredient in the compositions of this invention, the 2-hydroxy-1-amino alkanes also improve the deteregnt properties of detergent compositions containing as the active detergent ingredient the other water soluble salts of alkylbenzene sulfonic acid such as, for example, the corresponding water soluble potassium, magnesium, ammonium, or alkylolamine salts. Individual alkylbenzene sulfonates such as, for example, dodecylbenzene sulfonate may be used as the active detergent 3,296,146 Patented Jan. 3, 1967 "ice ingredient, or there may be used a mixture of alkylbenzene sulfonates wherein the length of the alkyl group varies such as, for example, a mixture of compounds wherein the alkyl-benzene sulfonates have alkyl groups that contain from 9 to 15 carbon atoms. When utilizing a mixture of alkylbenzene sulfonates it is preferred that the average carbon content of the alkyl group range from about 11 to 13.

Preparation of alkylbenzene s-ulfonates is well known to those skilled in the art. Generally the branched chain compounds are derived from an alkylbenzene that has been prepared by alkylating benzene with a suitable carbon content propylene polymer in the presence of aluminum chloride alkylation catalyst to obtain substantial yields of mono-alkylated benzene. On the other hand, the straight chain compounds are generally derived from an alkylbenzene that has been prepared by alkylating benzene with a suitable chain length halogenated normal parafiin in the presence of aluminum chloride alkylation catalyst. Sulfonation of the straight or branched chain alkylated benzenes may be accomplished utilizing sul fonating agents such as sulfuric acid, oleum, or sulfur trioxide. The resulting alkylbenzene sulfonic acids are then neutralized with any salt forming base such as, for example, the alkali metal hydroxides, alkaline earth metal oxides, or alkanol amines including mono-, di-, or triethanolamine, which give a water soluble alkylbenzene sulfonate.

It is well known to utilize alkylbenzene sulfonates as described herein in built formulations which contain substantial amounts of water soluble inorganic salts and which may also contain small amounts of other inorganic and organic compounds which perform as redeposition agents, anti-caking agents, corrosion inhibitors, etc. In such compositions the amount of alkylbenzene sulfonate present should range from about 10 to about 30 weight percent based on the total weight of the composition.

The Z-hydroxy-l-amino alkanes which are effective in improving the detergent properties of alkylbenzene sulfonate detergent compositions are characterized by the formula R-CHCH ()H b IH wherein R is an alkyl group which contains from about 4 to about 18 carbon atoms. It is preferred that the alkyl group, R, be straight chain in structure; however, it may also be branched chain in structure. Mixtures of the above described hydroxy amino alkanes may be utilized to obtain the improved detergency properties. Exemplary hydroxy amino alkanes are Z-hydroxy-l-amino hexane; Z-hydroxy-l-amino octane; Z-hydroxy-l-amino dodecane; 2-hydroxy-1-amino octadecane, and thelike, and any branched chain isomers'thereof. The preferred hydroxy amino alkanes are those whichhave a total carbon content ranging from 8 to 12 inclusive with the alkyl group, R, being of straight chain structure, i.e. 2-hydr-oxy-l-amino octane; 2-hydroxy-1-amino nonane, etc., up to and including 2-hydroxy-1-amino dodecane.

The hydroxy amino alkanes described above, to be effective in improving the detergency properties of alkylbenzene sulfonate detergent compositions, should be present in an amount ranging from about 0.3 to about 3.3 weight percent and preferably about 1 weight percent based on the amount of alkylbenzene sulfonate present. When utilized to improve the detergency properties of built detergent compositions containing from about 10 to about 30 weight percent of alkylbenzene sulfonates, effective amounts of the Z-hydroxy-l-amino alkane range from about 0.03 to about 1.0 weight percent based on the total weight of the composition, but inamounts not less than about 0.3 weight percent nor in excess of about 3.3 weight percent of the alkylbenzene sulfonate present. It has been found that as the concentration of the higher molecular weight hydroxy amino alkanes, i.e. those containing in the neighborhood of about 12 and a higher number of carbon atoms, exceeds about 3.3 weight percent of the alkylbenzene sulfonate present, the detergency values of the compositions are reduced rather than increased and, in addition, the foaming properties of the composition are deleteriously affected. For example, a built detergent formulation containing about 5 weight percent of Z-hydroxy-l-amino dodecane based on the amount of sodium alkylbenzene sulfonate present has detergency and foam values of respectively 30 and 50 percent less than formulations without this hydroxy amino alkane. On the other hand, the lower molecular weight hydroxy amino alkanes can be used in larger amounts, i.e. in excess of about 3.3 weight percent of the alkylbenzene sulfonate present without loss of detergency or foaming values but nevertheless without any corresponding increase in these values. For example, a built detergent formulation containing about 5 weight percent Z-hydroxy-l-amino octane based 'on the amount of sodium alkylbenzene sulfonate present has approximately the same detergency and foam values as a built detergent formulation containing about 2 weight percent of this hydroxy amino alkane. It should also be pointed out that hydroxy amino alkanes having a carbon content of less than about 6 are quite ineffective in improving the detergency properties of alkylbenzene sulfonate detergent compositions. For example, built detergent formulations containing 0.5 weight percent and 3 weight percent respectively of 2-hydroxy-l-amino ethane based on the amount of sodium alkylbenzene sulfonate present had no appreciable increase in detergency values as compared to corresponding compositions containing no hydroxy amino ethane. In addition these compositions showed that the, addition of the hydroxy amino ethane had :a deleterious effect on the foaming properties of the compositions. It should be pointed out that alkylbenzene sulfonate detergent compositions containing the detergency improving agents of this invention in the amounts specified herein have substantially the same foaming values as those compositions without the hydroxy amino alkane.

The preparation by various methods of 2-hydroxy-1- amino alkanes is well known to those skilled in the art. For example, they may be prepared by reacting a 1,2- alkylene oxide of suitable chain length and structure with ammonia at a temperature ranging from 120 C. to 200 C. in the presence preferably of water or a low molecular weight alcohol, e.g. methyl or ethyl alcohol. They also may be prepared by reacting a suitable chain length alphaolefin with nitrogen dioxide and successively hydrolyzing and hydrogenating the reaction product.

A particularly desirable way for preparing nitro alcohols from which the 2-hydroxy-1-amino alkanes of this invention can be derived is disclosed in U.S. Patent No. 3,192,- 248 to Bonetti et al. In this patent there is described an efficient process for preparing a mixture of nitronitrites of the formula and dinitroparaflins of the formula by reacting an equilibrium mixture of N0 and N 0 with an alpha-olefin of the formula RCH=CH wherein R in each of the formulas is a straight chain alkyl radical containing 1 to 22 carbon atoms. The nitronitrite produced is then hydrolyzed to the corresponding nitroalcohol. It is unnecessary to separate the nitronitrite from the mixture prior to hydrolyzing because it is much more unstable than the dinitroparafiin and accordingly hydrolyzes readily to the nitroalcohol which can then be more easily separated from the dinitroparaflin than the nitronitrite. the nitronitrite is then separated from the dinitroparafiin by any suitable means, e.g., by silica gel chromatography and reduced to the corresponding 2-hydroxy-1-amino alkane by any of the standard hydrogenation techniques.

The discovery that 2-hydroxy-1-amino alkanes of this invention impart improved detergency properties to water soluble alkylbenzene sulfonates can best be taken advantage of in built alkylbenzene sulfonate detergent formulations. In this regard any of the customarily employed water soluble inorganic salt builders can be combined with the detergency improving agents of this invention and.

water soluble alkylbenzene sulfonates to prepare improved built detergent formulations. Exemplary builders that can be utilized are the neutral salts of the strong inorganic acids such as, for example, sodium chloride and sodium sulfate; the allcaline salts of the weak inorganic acids such as, for example, the alkali metal phosphates and carbonates. In addition to these builders smaller amounts of other inorganic and organiccompounds that perform specific functions may also be utilized in the compositions. For instance, corrosion inhibitors, e.g. sodium silicate, anti-redeposition agents, e.g. carboxymethylcellulosaand any of the normally used anti-caking agents, dyes, perfumes, optical brighteners, bleaches, etc. can be included in the formulation. The builders and other functional additives generally will comprise from about 70 weight percent to about weight percent of the composition.

The built detergent formulations can be utilized in solid form, e.g. powdered or granular, or in liquid form. When used in liquid formulations, the percent solids present generally should comprise from about 40 to about 45 weight percent of the formulation and in addition it will be advantageous to have phosphate builders present in their.

various alkali metal salt forms such as, for example, a

mixture of sodium tripolyphosphate and tetra potassium pyrophosphate thereby increasing the water solubilityof the composition. xylene sulfonate, also may be added to the built liquid composition to impart increased water solubility properties to the composition.

To illustrate the improved detergency properties of the compositions of this invention there is included in the table below the results of exemplary tests which were carried out to evaluate the detergency properties of various deter.- gent compositions. The test procedure and method for calculating the detergency values is described in detail in the co-pending application of Meyers et al, entitled Polyalkoxyhydroxyamines, filed September 19, 1962, Serial No. 224,836, now Patent 3,207,791. Generally, the tests consist of washing a soiled cotton cloth in a launderometer in the presence of an aqueous solution containing 0.3 weight percent solids. of a built powder detergent formulation which was comprised of in weight percent 40 percent of sodium tripolyphosphate, 7 percent of sodium silicate, 1 percent carboxymethylcellulose, 22 percent of sodium sulfate, with the remaining 30 percent of the com-' position being made up of sodium branched chain C -C alkylbenzene sulfonate wherein the alkyl chain has an average carbon content of about 12, or a mixture of this sulfonate and the 2-hydroxy-l-amino alkane identified in the table below and present in amounts as shown in the table. Thus the percent of alkylbenzene sulfonate present in the built composition is 30 percent minus the percent of hydroxy amino alkane indicated in the table. After washing the cloths their degree of cleanliness was read photometrically and the detergency values of the compositions were calculated and related to a standard anionic detergent composition that arbitrarily was assigned a detergency value of 70. The results of the tests are shown 1 in the tabl below.

The nitroalcohol produced by hydrolyzing.

Hydrotropes such as, for example,

1 Concentration of detergency improving agent in wt. percent based on the total weight of the built powder composition,

The foregoing table clearly shows the improvements in the detergent properties of the compositions of this invention. It should be particularly noted that the improved detergency values are obtained with surprisingly small amounts of the hydroxy amino alkane. Other known detergency improving agents used in conjunction with alkylbenzene sulfonates must normally be present in quite larger amounts to obtain comparable increases in the detergency values.

We claim:

1. A detergent composition having improved detergency properties comprising a water soluble alkylbenzene sulfona-te having 9 to 15 carbon atoms in the alkyl side chain and as a detergency improving agent, 2-hydroxy-1-amino alkane of the formula wherein R is an alkyl radical having from about 4 to about 18 carbon atoms and wherein the detergency improving agent is present in an amount ranging from about 0.3 weight percent to about 3.3 weight percent based on the amount of the water soluble alkylbenzene snlfonate present.

2. A detergent composition in accordance with claim 1 wherein said R is straight chain in structure.

3. A detergent composition in accordance with claim 1 wherein said hydroxy amino alkane is present in an amount of about 1 weight percent based on the amount of alkylbenzene sulfonate present.

4. A detergent composition in accordance with claim 1 wherein the alkyl group of the alkylbenzene sulfonate is branched chain in structure.

5. A detergent composition in accordance with claim 4 wherein said sulfonate is sodium alkylbenzene sulfonate.

6. A detergent composition having improved detergency properties consisting essentially of in weight percent based on the total weight of the composition:

(a) about to about 30 percent of water soluble alkylbenzene sulfonate having 9 to carbon atoms in the alkyl side chain,

(b) about 0.03 to about 1 percent of Z-hydroxy-l-amino alkane of the formula:

wherein R is an alkyl radical having from about 4 to about 18 carbon atoms and wherein said hydroxy amino alkane is present in an amount ranging from about 0.3 to about 3.3 weight percent of said alkylbenzene sulfonate, and,

(0) about to about percent of detergent builder.

7. A detergent composition in accordance with claim 6 wherein said R is straight chain in structure.

8. A detergent composition in accordance with claim 6 wherein said hydroxy amino alkane is present in an amount of about 1 weight percent based on the amount of alkyl-- benzene sulfonate present.

9. A detergent composition in accordance with claim 6 wherein the alkyl group of the alkylbenzene sulfonate is branched chain in structure.

10. A detergent composition in accordance with claim 9 wherein said sulfonate is sodium allrylbenzene sulfonate.

11. A detergent composition having improved detergency properties consisting essentially of in weight percent based on the total weight of the composition:

(a) 29.7 percent of sodium alkylbenzene sulfonate having a branched alkyl side chain containing from 9 to 15 carbon atoms and having an average carbon content of about 12, (b) 0.3 percent of a 2-hydroxy-1-amino alkane of the formula wherein R is a straight chain alkyl radical containing from about 4 to about 18 carbon atoms, and, (c) 70 percent of detergent builders comprised of 40 percent of sodium tripolyphosphate, 22 percent of sodium sulfate, 7 percent of sodium silicate, and 1 percent of 'carboxymethylcellulose. 12. A detergent composition in accordance with claim 11 wherein said R contains 6 to 10 carbon atoms.

13. A detergent composition in accordance with claim 12 wherein said R contains 6 carbon atoms.

14. A detergent composition in accordance with claim 12 wherein said R contains 10 carbon atoms.

No references cited.

LEON D. ROSDOL, Primary Examiner.

S. E. DARDEN, Assistant Examiner. 

1. A DETERGENT COMPOSITION HAVING IMPROVED DETERGENCY PROPERTIES COMPRISING A WATER SOLUBLE ALKYLBENZENE SULFONATE HAVING 9 TO 15 CARBON ATOMS IN THE ALKYL SIDE CHAIN AND AS A DETERGENCY IMPROVING AGENT, 2-HYDROXY-1-AMINO ALKANE OF THE FORMULA 